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Publication numberUS20060108905 A1
Publication typeApplication
Application numberUS 11/117,324
Publication date25 May 2006
Filing date29 Apr 2005
Priority date25 Nov 2004
Also published asUS8846159, US20130045336
Publication number11117324, 117324, US 2006/0108905 A1, US 2006/108905 A1, US 20060108905 A1, US 20060108905A1, US 2006108905 A1, US 2006108905A1, US-A1-20060108905, US-A1-2006108905, US2006/0108905A1, US2006/108905A1, US20060108905 A1, US20060108905A1, US2006108905 A1, US2006108905A1
InventorsHan Cho, Yong Park, Joon Park, Young Son
Original AssigneeSamsung Electronics Co., Ltd.
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Mold for fabricating barrier rib and method of fabricating two-layered barrier rib using same
US 20060108905 A1
Abstract
The disclosed mold includes recessed parts which have a shape corresponding to embossed portions of the barrier rib to be fabricated, and protruding parts which have a shape corresponding to depressed portions of the barrier rib to be fabricated, protrude adjacent to the recessed parts, and are tapered. The protruding parts and the recessed parts are arranged at regular intervals. It is possible to simply fabricate the two-layered barrier rib for inkjet application through a single embossing process at low cost using the mold for fabricating the barrier rib of the present invention.
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Claims(18)
1. A mold for fabricating a barrier rib, comprising:
a plurality of protruding parts; and
a plurality of recessed parts,
wherein, the protruding parts and the recessed parts are arranged at regular intervals, the recessed parts have a shape corresponding to embossed portions of the barrier rib to be fabricated, and the protruding parts have a shape corresponding to depressed portions of the barrier rib to be fabricated, protrude adjacent to the recessed parts, and are tapered.
2. The mold as set forth in claim 1, wherein the mold is made of material selected from the group consisting of metal, semiconductors, and insulating material, and edges of the protruding parts have one of a shape which is formed by two sides meeting at a predetermined angle and a rounded shape.
3. A method of fabricating a two-layered barrier rib, comprising:
(i) applying ink-philic material on a transparent substrate to form a lower ink-philic layer;
(ii) applying ink-phobic material on the ink-philic layer to form an upper ink-phobic layer;
(iii) providing the mold for fabricating the barrier rib according to claim 1 on the ink-phobic layer and leaving a resulting structure for a predetermined time;
(iv) radiating UV or applying heat onto a backside of the transparent substrate to conduct curing; and
(v) removing the mold.
4. The method as set forth in claim 3, wherein viscosity of the ink-phobic material is lower than viscosity of the ink-philic material.
5. The method as set forth in claim 3, further comprising applying at least one of heat and pressure after the mold is provided in the step (iii).
6. The method as set forth in claim 3, wherein the ink-philic layer is made of hydrophilic material and the ink-phobic layer is made of hydrophobic material when a hydrophilic ink is used, and the ink-philic layer is made of the hydrophobic material and the ink-phobic layer is made of the hydrophilic material when an oily ink is used.
7. The method as set forth in claim 4, wherein the ink-philic layer is made of hydrophilic material and the ink-phobic layer is made of hydrophobic material when a hydrophilic ink is used, and the ink-philic layer is made of the hydrophobic material and the ink-phobic layer is made of the hydrophilic material when an oily ink is used.
8. The method as set forth in claim 6, wherein the hydrophobic material is one or more copolymers selected from the group consisting of isoprene, styrene, acrylate containing fluorine, methacrylate containing fluorine, monomers thereof, oligomers thereof, homopolymers or copolymers thereof, and organic or inorganic complexes containing silicon.
9. The method as set forth in claim 6, wherein the hydrophilic material is material selected from the group consisting of polyethylene glycol-, polyurethane-, polyamide-, and poly(2-hydroxy ethyl methacrylate)-based homopolymer or copolymer.
10. The method as set forth in claim 7, wherein the hydrophobic material is one or more copolymers selected from the group consisting of isoprene, styrene, acrylate containing fluorine, methacrylate containing fluorine, monomers thereof, oligomers thereof, homopolymers or copolymers thereof, and organic or inorganic complexes containing silicon.
11. The method as set forth in claim 7, wherein the hydrophilic material is material selected from the group consisting of polyethylene glycol-, polyurethane-, polyamide-, and poly(2-hydroxy ethyl methacrylate)-based homopolymer or copolymer.
12. The method as set forth in claim 3, further comprising surface treating or coating a surface of the mold using material constituting the ink-philic layer.
13. The method as set forth in claim 4, further comprising surface treating or coating a surface of the mold using material constituting the ink-philic layer.
14. The method as set forth in claim 3, further comprising conducting cooling to achieve curing between the steps (iii) and (iv) when one or both of the ink-phobic material and the ink-philic material are thermoplastic material.
15. A barrier rib fabricated according to the method of claim 3.
16. The barrier rib as set forth in claim 15, wherein the barrier rib is used to fabricate one of a color filter for flat panel displays, an organic light emitting display, and an organic thin film transistor, using an inkjet printing process.
17. The barrier rib as set forth in claim 15, wherein the barrier rib is used for a display part of one of a flat panel display, including an electrophoresis display and an electrowetting display, a PDP or a flexible display.
18. The barrier rib as set forth in claim 15, wherein the barrier rib is used for a combinatorial test plate.
Description
    BACKGROUND OF THE INVENTION
  • [0001]
    Priority is claimed to Application No. 2004-97649, filed in the Republic of Korea on Nov. 25, 2004, herein incorporated by reference.
  • [0002]
    1. Field of the Invention
  • [0003]
    The present invention relates, in general, to a mold for fabricating a barrier rib and a method of fabricating a two-layered barrier rib using the same and, more particularly, to a mold for fabricating a barrier rib that includes a plurality of tapered protruding parts and recessed parts having a shape corresponding to embossed portions of the barrier rib, and a method of fabricating a two-layered barrier rib for inkjet application using the same through a low-cost simple process.
  • [0004]
    2. Description of the Related Art
  • [0005]
    As shown in FIG. 1, a conventional barrier rib for display devices has a vertically and horizontally striped structure so as to discriminate RGB pixels on a transparent glass substrate 2. A space between the barrier ribs is empty and the adjacent surface is flat and transparent to at least one wavelength so that light penetrates it. In a color filter for liquid crystal displays, an organic black matrix formed on the glass substrate may be exemplified as an application of barrier rib structure.
  • [0006]
    Methods of fabricating the color filter for liquid crystal displays is classified into various methods, such as a pigment dispersion method, a printing method, a dyeing method, an electrode position method, a photolithographic method, and an inkjet printing method. Among them, the inkjet printing method has drawn much attention from the display industries in recent years because it has advantages in that, since it is possible to simultaneously produce red (R), green (G), and blue (B) color filters, the process is simple, the amount of material used is reduced, and thus the production cost is low.
  • [0007]
    According to the inkjet printing method, predetermined patterns, what is commonly called a barrier rib structure formed on a substrate, are prepared and the recessed parts of the barrier rib are filled with colored resins (R, G, and B) to fabricate a color filter. When an embossing process or an imprinting process employed for fabricating barrier ribs, a deformable composition for the barrier rib is pressed using the mold having a predetermined pattern, and cured, and the mold is removed, thereby forming the barrier rib structure on the substrate. In other words, it is possible to apply the embossing process to fabricate a micropattern or a barrier rib. The embossing process may be classified into a thermal embossing process, in which curing is conducted by temperature variation, and a UV embossing process, in which curing is conducted by UV radiation, according to a method of forming a solidified pattern. In the thermal embossing process, if material of the barrier rib is thermoplastic, the material is heated at a glass transition temperature or higher so as to be deformable or fluidic at the molding temperature, pressure is applied thereto to conduct embossing, the resulting material is solidified (more strictly speaking, glassified) by cooling after a pattern is formed, and the mold is removed. Meanwhile, when using thermosetting material, the material of the barrier rib having fluidity is embossed, heated, and cured, and then the mold is removed.
  • [0008]
    With respect to a conventional method of preventing the nonuniform spread or mix-up between the adjacent pixels and staining of the barrier rib's surface by resins of color filter printed in an inkjet manner, Japanese Patent Laid-Open Publication No. 2001-42313 discloses a method of neatly applying ink to an ink receiving structure between barrier ribs (see FIG. 2).
  • [0009]
    In other words, as shown in FIG. 2, a barrier rib is patterned on a glass substrate 11 using photolithographic methods so as to have a structure consisting of two layers 12, 13. A lower layer 12 of the barrier rib is made of a hydrophilic material that has affinity to hydrophilic ink and an upper layer 13 is made of hydrophobic material that has an aversion for ink so that the glass substrate 11 easily receives ink, and vice versa in the case of water-based ink. However, if the barrier rib is fabricated through the above methods, undesirably, a plurality of complicated coatings, mask aligning steps and exposure processes must be carried out.
  • [0010]
    Furthermore, there exist methods of employing materials having different surface properties or of conducting treatment using them so as to easily receive ink through a procedure similar to that of Japanese Patent Laid-Open Publication No. 2001-42313 as described above. For example, Japanese Patent Laid-Open Publication No., 2000-89022 discloses a method of conducting exposure while an ink receiving layer is hidden using a black matrix made of a resin composition having a light blocking property. Japanese Patent Laid-Open Publication No. 2000-28819 discloses a method of polishing an ink receiving layer to flatten it, Japanese Patent Laid-Open Publication No. Hei. 11-194211 discloses a method of forming a second layer on a metal black matrix. Korean Patent Laid-Open Publication No. 2001-110183 discloses a surface treatment method using a plasma.
  • [0011]
    However, all of the above methods need at least one additional photolithography process which incurs a high cost, particularly because of a surface treatment or the use of costly devices and fine chemicals in great quantities. Therefore, there remains a need to develop a mold capable of fabricating a barrier rib employing a simple low-cost process and an embossing method of fabricating the barrier rib using the mold.
  • SUMMARY OF THE INVENTION
  • [0012]
    The present inventors have conducted extensive studies into the solutions of problems occurring in the prior art, resulting in the finding that, when employing a mold for fabricating a barrier rib, which includes a plurality of tapered protruding parts and a plurality of recessed parts, and an embossing process according to the present invention, it is possible to relatively simply fabricate a two-layered barrier rib for inkjet applications, which includes an ink-philic layer and an ink-phobic layer, through a single embossing process, thereby accomplishing various aspects of the present invention.
  • [0013]
    Therefore, an object of the present invention is to provide a mold for fabricating a barrier rib, which is capable of fabricating a two-layered barrier rib through a single embossing process.
  • [0014]
    Another object of the present invention is to provide a method of relatively simply fabricating the two-layered barrier rib which includes an ink-philic layer and an ink-phobic layer using the mold for fabricating the barrier rib through the single embossing process.
  • [0015]
    Still another object of the present invention is to provide a two-layered barrier rib for inkjet application fabricated through the above method of fabricating the barrier rib.
  • [0016]
    In order to accomplish the above objects, according to an aspect of the present invention, there is provided a mold for fabricating a barrier rib. The mold comprises a plurality of protruding parts and a plurality of recessed parts. The protruding parts and the recessed parts are arranged at regular intervals, and the recessed parts have a shape corresponding to embossed ink barrier portions to be fabricated. The protruding parts have shapes corresponding to depressed portions of the barrier rib to be fabricated, protrude adjacent to the recessed parts, and are tapered, therefore each protruding part of the mold has a triangular loop-like shape (See FIGS. 3 a and 3 b). This tapered shape of the mold makes the process simple as shown in later. Accordingly, the surface of recessed part of embossed barrier rib structure is not flat rather grooved, however, it is almost flat as long as the apex angle of the top of the protruding part is not much less than 180°.
  • [0017]
    According to another aspect of the present invention, there is provided a method of fabricating a barrier rib. The method comprises (i) applying ink-philic material on a transparent substrate to form a lower ink-philic layer; (ii) applying ink-phobic material on the ink-philic layer to form an upper ink-phobic layer; (iii) providing the mold for fabricating the barrier rib according to claim 1 on the ink-phobic layer and leaving the resulting structure for a predetermined time; (iv) radiating UV onto the backside of the transparent substrate or applying heat to conduct curing; and (v) removing the mold.
  • [0018]
    According to still another aspect of the present invention, there is provided a barrier rib fabricated through the above method.
  • BRIEF DESCRIPTION OF THE DRAWINGS
  • [0019]
    The above and other objects, features and advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
  • [0020]
    FIG. 1 schematically illustrates a barrier rib for displays;
  • [0021]
    FIG. 2 is a schematic sectional view of a conventional two-layered barrier rib;
  • [0022]
    FIG. 3 a illustrates a three-dimensional structure of a mold for fabricating a barrier rib, according to embodiments of the present invention;
  • [0023]
    FIG. 3 b is a sectional view taken along the line A-A′ of FIG. 3 a;
  • [0024]
    FIGS. 3 c and 3 d are confocal laser scanning microscope images which show the three-dimensional structure of the mold for fabricating the barrier rib, and the embossed structure after completion of embossing process, according to embodiments of the present invention, respectively;
  • [0025]
    FIGS. 4 a-4 e illustrates the fabrication of a two-layered barrier rib using the mold for fabricating the barrier rib, according to embodiments of the present invention;
  • [0026]
    FIG. 5 illustrates the mold in an embossing step and deformation of a two layers in the course of fabricating the two-layered barrier rib according to embodiments of the present invention;
  • [0027]
    FIGS. 6 a and 6 b are SEM pictures of the barrier rib fabricated according to the present invention;
  • [0028]
    FIG. 7 a illustrates Raman spectrum of ORMOCER used as an ink-philic material according to embodiments of the present invention to probe the presence of ink-phobic material HEMA on the ink-philic section;
  • [0029]
    FIG. 7 b illustrates the barrier rib used in the Raman image mapping measurement;
  • [0030]
    FIG. 7 c illustrates two-dimensional micro-Raman mapping results of a patterned section of FIG. 7 a; and
  • [0031]
    FIG. 7 d is a graph of Raman intensity of ORMOCER in the direction of the arrow of FIG. 7 b.
  • DESCRIPTION OF THE PREFERRED EMBODIMENTS
  • [0032]
    Hereinafter, a detailed description will be given of the present invention, referring to the accompanying drawings.
  • [0033]
    The present invention relates to a mold which is used to fabricate a barrier rib, such as an organic black matrix of an inkjetted color filter for a liquid crystal display. In the mold of the present invention, since a protruding part protrudes adjacent to a recessed part and is tapered, two deformable layers having different ink-philicity constituting the barrier rib is pressed and solidified at the same time, thus it is possible to simply fabricate a two-layered barrier rib using a single embossing process at a low cost.
  • [0034]
    FIG. 3 a illustrates a three-dimensional structure of the mold for fabricating the barrier rib according to the present invention. With reference to FIG. 3 a, a mold 30 for fabricating the barrier rib according to the present invention includes a predetermined pattern 31 in which a plurality of protruding parts 31 a and a plurality of recessed parts 31 b are repeatedly arranged at regular intervals. As shown in FIG. 3 b, the protruding parts 31 a have a shape corresponding to depressed portions of the barrier rib to be fabricated, protrude adjacent to the recessed parts 31 b, and are tapered, therefore has a pentahedral triangular loop-like shape. FIG. 3 c is confocal laser scanning microscope image which shows the three-dimensional structure of the mold for fabricating the barrier rib, according to embodiments of the present invention, and FIG. 3 d is the embossed structure after completion of the present process. As shown in FIG. 3 c, edges of the protruding parts 31 a of the mold according to embodiments of the present invention may have a pointed shape which is formed by meeting two sides at a predetermined angle, or a rounded edge shape, if necessary. In exemplary embodiments of the present invention, the mold may be made of any material, such as silicon, metal, plastic, glass, semiconductor, or insulating material.
  • [0035]
    The fabricating method of the mold of the present invention having tapered protruding parts includes well-known conventional fabrication techniques for three-dimensional micro electromechanical systems (MEMS) such as a holographic lithography, anisotropic wet etching, LIGA, direct laser writing using excimer laser and so forth.
  • [0036]
    Another aspect of the present invention is characterized in that the mold for fabricating the barrier rib and an embossing process are employed to fabricate a two-layered barrier rib for inkjet application which includes an ink-philic layer and an ink-phobic layer. Hereinafter, a method of fabricating the two-layered barrier rib will be exemplified, but the method of the present invention may be applied to a multilayered barrier rib having two or more layers.
  • [0037]
    FIG. 4 illustrates the fabrication of a barrier rib using a mold 21 for fabricating the barrier rib according to the present invention through a single embossing process. With reference to FIG. 4, in order to fabricate a two-layered barrier rib for inkjet application using the mold 21 for fabricating the barrier rib according to the present invention, ink-philic material is applied on a transparent substrate 24 to form an ink-philic layer (“lower layer”: 23), and ink-phobic material is then applied on the ink-philic layer 23 to form an ink-phobic layer (“upper layer”: 22).
  • [0038]
    Material for the transparent substrate which is used to fabricate the barrier rib of the exemplary embodiments of the present invention is not limited, and may be properly selected from an inorganic substrate and an organic substrate, depending on the application of the barrier rib. The substrate is not necessarily transparent when the hot embossing method is employed, however, transparent substrate is chosen as a representative example because the main application area of the present invention is display-related one.
  • [0039]
    The method of forming the ink-phobic layer 22 or the ink-philic layer 23 is not limited, and a suitable method (for example, a spin coating method or a dip coating method) may be chosen according to circumstances.
  • [0040]
    When using a hydrophilic ink such as water or alcohol based solutions, the ink-philic layer 23 is made of hydrophilic material, and the ink-phobic layer 22 is made of hydrophobic material. When using an oily ink, the ink-philic layer 23 is made of the hydrophobic material, and the ink-phobic layer 22 is made of the hydrophilic material.
  • [0041]
    According to the processing feature of the present invention, the viscosity of the lower layer must be higher than that of the upper layer when the mold is pressed to maintain the desirable two-layer structure. Therefore, material having lower viscosity at a molding temperature is used as the ink-phobic material constituting the ink-phobic upper layer 22, and material having higher viscosity at a molding temperature is used as the ink-philic material constituting the ink-philic lower layer 23. The viscosity of each layer can be selected by controlling their composition or degree of polymerization.
  • [0042]
    Illustrative, but non-limiting examples of the hydrophobic materials available to the present invention include isoprene, styrene, acrylate containing fluorine, methacrylate containing fluorine, monomers thereof, oligomers thereof, homopolymers or copolymers thereof, or organic or inorganic complexes containing silicon. Preferably, the hydrophobic material is exemplified by ORMOCER which is manufactured by Microresist Co., Germany.
  • [0043]
    Illustrative, but non-limiting examples of the hydrophilic material available to the present invention include polyethylene glycol, polyurethane, polyamide, poly(2-hydroxy ethyl methacrylate), monomers thereof, oligomers thereof, or homopolymers or copolymers thereof.
  • [0044]
    Inorganics, such as silicone subjected to surface modification or carbon nanotubes, may be added to the ink-phobic layer 22 and the ink-philic layer 23 so as to control hydrophilic and hydrophobic properties, but the kind of material is not limited. Additionally, in the present invention, a UV initiator (for example, Irgacure 184), a heat initiator (for example, AIBN: 2,2′-Azobisisobutyronitrile), a crosslinking agent, a pigment, a dye, and a surfactant may be added to the ink-phobic layer composition or the ink-philic layer composition, if necessary, but their kind is not limited. Material that is more flexible than the mold 21 for fabricating the barrier rib and is deformable or fluidic is used as material for forming the ink-phobic layer 22 and the ink-philic layer 23.
  • [0045]
    After the ink-philic layer 23 and the ink-phobic layer 22 are formed on the transparent substrate 24, the ink-phobic layer 22 is positioned so as to face protruding parts of the mold 21 for fabricating the barrier rib according to exemplary embodiments of the present invention. The mold comes into contact with the ink-phobic layer 22 while heat, or pressure, or heat and pressure are applied thereto, if necessary, and then left for a predetermined time. As shown in FIG. 4 b, if the mold 21 for fabricating the barrier rib is positioned on the ink-phobic layer 22 and a predetermined pressure is then applied thereto to deform material of the ink-phobic layer 22, stress is focused only on the ink-phobic layer 22 because the material of the ink-phobic layer 22 has lower viscosity than the material of the ink-philic layer 23, thus only the ink-phobic layer 22 deforms or flows as shown at reference number 25. In this respect, the applied pressure may depend on the desired height of the barrier rib.
  • [0046]
    As shown in FIG. 4 c, even though deformation occurs after the mold comes into contact with the lower layer, the upper layer and the lower layer do not mix with each other because of a difference in viscosity and hydrophilicity, and the final deformation is assured while the upper and the lower layer are maintained as they are after a predetermined time (FIG. 3 d).
  • [0047]
    As shown in FIG. 4 d, UV 26 irradiates to the backside of the transparent substrate or heat is applied particularly to the resins to cure the barrier rib, and then the mold is removed, thereby creating a structure as shown in FIG. 4 e, in which an ink receiving layer 28 a having an affinity to ink is formed on a transparent substrate, an ink-philic barrier rib portion 28 b having an affinity to ink is formed below the barrier rib, and the barrier rib 27 having an aversion for ink is formed thereon.
  • [0048]
    In the present invention, it is possible to adjust the height of the ink-philic barrier rib portion 28 b or to remove it by controlling the amount of material of the ink-philic layer of FIG. 4 a or controlling the pressure applied to the mold, depending on the purpose.
  • [0049]
    FIG. 5 illustrates the mold in an embossing step and deformation (flow) of two layers. If the mold is subjected to a surface treatment process or a coating process so as to have a hydrophilic or hydrophobic property like the ink-philic layer (lower layer), the ink-phobic layer (upper layer) having the low viscosity meets the mold at a high angle of θ between the mold having an affinity for ink and the lower layer, thus the mechanical mixing of the upper and the lower layer does not take place during the embossing unless the pressing speed is not fast. Furthermore, the Reynolds number of the upper layer has the following value under typical embossing conditions: Re LV ρ η ( 1 × 10 - 5 m ) ( 1 × 10 - 5 m sec - 1 ) ( 10 3 kg / m 3 ) ( 10 - 2 kgm - 1 sec - 1 ) ~ 10 - 5 Equation 1
  • [0050]
    Therefore, Re is low enough to guarantee an absence of vortex, turbulence or a secondary flow during embossing. In other words, the flow is a stable and laminar flow. In addition, the possibility of the presence of a residual top resin on the outer surface of the bottom layer is significantly lowered.
  • [0051]
    After the mold of exemplary embodiments of the present invention is left for a predetermined time, typically from zero to several tens of seconds, UV irradiates to the backside of the transparent substrate or heat is applied to cure the ink-philic layer composition and the ink-phobic layer composition. Finally, the mold is removed, thereby fabricating the barrier rib of the present invention.
  • [0052]
    The mold of embodiments of the present invention may be applied to a barrier rib, used to fabricate a color filter for liquid crystal displays, employing an inkjet printing method, a display part of a organic light emitting display, or an organic thin film transistor, a barrier rib for a display part of a flexible display, or an electrophoresis display or an electrowetting display, or a PDP cell, or a barrier rib for a combinatorial test plate.
  • [0053]
    A better understanding of the present invention may be obtained in light of the following examples which are set forth to illustrate, but are not to be construed to limit the present invention.
  • EXAMPLE 1 Fabrication of a Two-Layered Barrier Rib for an Inkjet Printing Color Filter, which has a Hydrophilic Lower Layer and a Hydrophobic Upper Layer, Through a UV Embossing Process
  • [0054]
    A monomer mixture liquid of 70 wt % aliphatic urethane-acrylate telechelic oligomer (Ebecryl 284 manufactured by UCB, Inc.) and 30 wt % hexanediol diacrylate (HDDA manufactured by UCB, Inc.), which had viscosity of 10,000 mPa·sec, as a solvent-free hydrophilic UV-curable material, was mixed with 0.75 wt % bisacylphosphine oxide (BAPO) as a photoinitiator based on the total monomer mixture liquid, and the resulting mixture was applied on a glass substrate having a thickness of 0.7 mm at 500 rpm for 30 sec to form an ink-philic layer (lower layer) having a thickness of 8 μm. 2,2,3,3-tetrafluoropropyl methacrylate monomer (viscosity of 10 mPa·sec) as hydrophobic UV curable material, which contained 0.1 wt % solvent-free fluorine-based surfactant (FC-430 manufactured by 3M Co.) and 1.0 wt % BAPO, was blade coated in a thickness of 1 μm to form an ink-phobic layer (upper layer). Subsequently, a mold for fabricating a barrier rib according to embodiments of the present invention as shown in FIG. 3 a was brought into close contact with the entire surface of the upper layer, pressure of 5 kgf/cm2 was applied thereto, and the resulting structure was left for 30 min. Thereafter, the backside of the glass substrate was exposed to UV of 1 kW for 3 min using a UV exposing machine, and the mold was then removed.
  • EXAMPLE 2 Fabrication of a Barrier Rib for an Inkjet Printing OLED, which has a Hydrophobic Lower Layer and a Hydrophilic Upper Layer, Through a UV/Hot Embossing Process
  • [0055]
    A surface of a mold was coated with a fluorine-based surfactant (Zonyl manufactured by DuPont, Inc.) and baked at 200□ so as to have a hydrophobic property. Poly(2,2,3,3-tetrafluoropropyl methacrylate) having a molecular weight of 100,000 (a glass transition temperature of about 66° C.) was dissolved in methylisobutylketone (MIBK) so as to have a concentration of 5 wt %, and applied on a glass substrate using a spin coater at a rotation rate of 2000 rpm to form a lower layer. 2-hydroxyethyl methacrylate oligomer, which was produced by dissolving Irgacure 184 and polymerizing it through UV polymerization until the viscosity was 1,000 mPa·sec, was applied thereon at a rotation rate of 2000 rpm. Subsequently, the mold for fabricating a barrier rib according to the present invention was brought into close contact with the entire surface of an upper layer, embossing was conducted while the temperature of the mold and the glass substrate was set to 145° C. and pressure was set to 5 kgf/cm2, and the resulting structure was left for 30 min. Thereafter, the backside of the glass substrate was exposed to UV of 1 kW for 3 min using a UV exposing machine, and the mold was then removed.
  • EXAMPLE 3 Fabrication of a Barrier Rib for an Inkjet Printing OLED, which has A Hydrophobic Lower Layer and a Hydrophilic Upper Layer, Through a UV Embossing Process
  • [0056]
    The surface of a mold was coated with a fluorine-based surfactant (Zonyl manufactured by DuPont, Inc.) and baked at 200° C. so as to have a hydrophobic property. ORMOCER B59 manufactured by Microresist Co., that is, hydrophobic organic/inorganic hybrid UV curable resin, was applied on a glass substrate using a spin coater at a rotation rate of 3000 rpm. 2-hydroxyethyl methacrylate (HEMA) monomer containing Irgacure 184 was applied thereon in drops of 1 ml using a pipette. Subsequently, the mold for fabricating a barrier rib according to the present invention was brought into close contact with the entire surface of an upper layer, embossing was conducted at room temperature and pressure of 5 kgf/cm2, the backside of the glass substrate was exposed to UV of 1 kW for 3 min using a UV exposing machine, and the mold was removed.
  • [0057]
    SEM pictures of the barrier rib fabricated in example 3 are shown in FIGS. 6 a and 6 b. As shown in FIGS. 6 a and 6 b, in the mold of the present invention, protruding parts are tapered and edges may have a rounded shape.
  • [0058]
    To evaluate the distribution of ORMOCER and HEMA in a section of the mold fabricated in example 3, two-dimensional micro-Raman image mapping measurement was conducted using Nanofinder 30 (Tokyo Instruments), and the results are shown in FIGS. 7 a to 7 d. As shown in FIG. 7 a, a peak corresponding only to ORMOCER was observed using the Raman spectrum. The section which was patterned so as to have the above peak was mapped in the direction of the arrow of FIG. 7 b, thereby obtaining two-dimensional distribution as shown in FIG. 7 c. Experimental conditions were set so that a diode laser was 785 nm, a point was 100, a step was 100, a shift speed was 2, and an exposure time was 0.5 sec. The intensity variation of ORMOCER in the direction indicated by the arrow in FIGS. 7 b and 7 c are shown in FIG. 7 d, and it can be confirmed that only HEMA was dispersed on the surface of the upper layer because the ORMOCER peak is almost 0 at the upper layer, and that only ORMOCER was dispersed on the lower layer because the ORMOCER peak is almost 100 at the lower layer. Accordingly, in the present invention, a two-layered barrier rib structure having different hydrophilicity is fabricated through a simple, single embossing process.
  • [0059]
    As described above, it is possible to fabricate a barrier rib comprising two layers having different physicochemical properties through a single low-cost process using a mold for fabricating the barrier rib of embodiments of the present invention without using complicated processes, costly lithography and high pressure devices. It is possible to easily and precisely form a pattern using the mold for fabricating the barrier rib, which has tapered protruding parts according to embodiments of the present invention.
Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US3103703 *27 Mar 195717 Sep 1963Continental Gummi Werke AgMold for producing flexible belts with teeth
US3323983 *8 Sep 19646 Jun 1967Kimberly Clark CoApparatus for embossing multi-ply paper sheets
US4174367 *23 Nov 197713 Nov 1979Breco Kunststoffverarbeitungs-Gmbh & Co. KgForm tool for production of a reinforced hose piece
US4464326 *24 Sep 19827 Aug 1984Fuji Rubber Co. Ltd.Method of manufacturing contact rubber structure
US4913639 *13 Sep 19883 Apr 1990Wheeler Robert GComposite caul plate
US4935184 *27 Jul 198919 Jun 1990PrimtecStabilized injection molding when using a common mold part with separate complimentary mold parts
US5954625 *4 Jun 199721 Sep 1999Industrial Engraving & Manufacturing, Corp.Method and apparatus for embossing continuous paper webs
US6036909 *25 Nov 199714 Mar 2000Kimberly-Clark Worldwide, Inc.Method for embossing web material using an extended nip
US6368097 *5 Aug 19999 Apr 20023M Innovative Properties CompanyApparatus for capping stem fasteners
US6677243 *31 May 200113 Jan 2004Canon Kabushiki KaishaMethod of manufacturing optical element
US6727970 *24 Sep 200127 Apr 2004Avery Dennison CorporationMethod of making a hybrid display device having a rigid substrate and a flexible substrate
US6846172 *7 Jun 200225 Jan 2005The Procter & Gamble CompanyEmbossing apparatus
US7071088 *23 Aug 20024 Jul 2006Molecular Imprints, Inc.Method for fabricating bulbous-shaped vias
US7099525 *25 Aug 200329 Aug 2006Georgia Tech Research CorporationDual-mode/function optical and electrical interconnects, methods of fabrication thereof, and methods of use thereof
US7112049 *12 Jan 200426 Sep 2006Daimlerchrysler AgDeep-drawing tool
US7168939 *26 Feb 200430 Jan 2007Hitachi Global Storage Technologies Netherlands BvSystem, method, and apparatus for multilevel UV molding lithography for air bearing surface patterning
US7261425 *3 Jan 200328 Aug 20073M Innovative Properties CompanyStructured surface articles containing geometric structures with compound faces and methods for making same
US7276278 *19 Sep 20022 Oct 20073M Innovative Properties CompanyImage covering laminate film and image projection sheet
US7320772 *15 Oct 200222 Jan 2008Sumitomo Bakelite Company, Ltd.System for embossing carrier tape and method for producing carrier tape
US20020139164 *19 Feb 20023 Oct 2002Ngk Insulators, Ltd.Press die for molding sipe blade and method of making the press die
US20020171026 *29 Nov 200121 Nov 2002Fujitsu LimitedMold, manufacturing method of a mold, manufacturing method of a recording medium and a substrate for such a recording medium
US20040038552 *23 Aug 200226 Feb 2004Watts Michael P.C.Method for fabricating bulbous-shaped vias
US20040042195 *15 Jul 20034 Mar 2004Hwang Jae HoDevice for forming groove pattern of light-guiding plate and method for forming groove pattern by using the same
US20040106346 *1 Jul 20033 Jun 2004Zafiroglu Dimitri PeterTextured composite material
US20040156108 *10 Dec 200312 Aug 2004Chou Stephen Y.Articles comprising nanoscale patterns with reduced edge roughness and methods of making same
US20050069603 *16 Nov 200431 Mar 2005Vaughn Jeffrey MossEmbossing apparatus
US20070090567 *14 Dec 200626 Apr 2007Hwang Jae HDevice for forming groove pattern of light-guiding plate and method for forming groove pattern by using the same
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US7404982 *14 Oct 200529 Jul 2008Seiko Epson CorporationColor filter forming method
US7544069 *28 Jul 20069 Jun 2009Lg Display Co., Ltd.Method for fabricating thin film pattern and method for fabricating flat panel display device using the same
US7754780 *9 Jun 200513 Jul 2010Lg Display Co., Ltd.Resist for forming pattern and method for forming pattern using the same
US7785504 *24 Jun 200531 Aug 2010Lg Display Co., Ltd.Thin film patterning apparatus and method of fabricating color filter array substrate using the same
US7977122 *31 Jan 200712 Jul 2011Roche Diagnostics Operations, Inc.Fluidic device containing 3D structures
US845504622 Jul 20104 Jun 2013Lg Display Co., Ltd.Thin film patterning apparatus and method of fabricating color filter array substrate using the same
US20050282402 *9 Jun 200522 Dec 2005Lg.Philips Lcd Co., Ltd.Resist for forming pattern and method for forming pattern using the same
US20060097414 *24 Jun 200511 May 2006Lg.Philips Lcd Co., Ltd.Thin film patterning apparatus and method of fabricating color filter array substrate using the same
US20060115749 *14 Oct 20051 Jun 2006Seiko Epson CorporationColor filter forming method
US20070145004 *28 Jul 200628 Jun 2007Jin Wuk KimMethod for fabricating thin film pattern and method for fabricating flat panel display device using the same
US20070184672 *31 Jan 20079 Aug 2007Roche Diagnostics Operations, Inc.Fluidic device containing 3d structures
US20080145966 *24 Oct 200719 Jun 2008National Taiwan UniversityMethod for fabrication of organic thin-film transistor
US20100291296 *22 Jul 201018 Nov 2010Gee Sung ChaeThin film patterning apparatus and method of fabricating color filter array substrate using the same
US20110223080 *24 May 201115 Sep 2011Roger SandozFluidic device containing 3d structures
Classifications
U.S. Classification313/292, 313/582, 313/495
International ClassificationH01J19/42, H01J1/88, H01J17/49
Cooperative ClassificationH01J2211/36, H01J9/242, G02F1/133512
European ClassificationH01J9/24B2, G02F1/1335F1
Legal Events
DateCodeEventDescription
19 Jul 2005ASAssignment
Owner name: SAMSUNG ELECTRONICS CO., LTD., KOREA, REPUBLIC OF
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:CHO, HAN SOL;PARK, YONG YOUNG;PARK, JOON YONG;AND OTHERS;REEL/FRAME:016544/0796
Effective date: 20050613
21 Sep 2012ASAssignment
Owner name: SAMSUNG DISPLAY CO., LTD., KOREA, REPUBLIC OF
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:SAMSUNG ELECTRONICS CO., LTD.;REEL/FRAME:029019/0139
Effective date: 20120904